Ionizer



FIG. 1 is a front elevational view of an ionizer according to our design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a top plan view thereof, the bottom plan view being a mirror image thereof; and,

FIG. 4 is a left side elevational view thereof, the right side elevational view being a mirror image thereof. 

The ornamental design for an “ionizer”, as shown and described. 